When an enhanced Node B (eNB) is newly or additionally installed, the eNB executes a self-configuration process. Self-configuration is an automated function for identifying a neighbor eNB, registering relationship setup, and setting up a connection to the core network in an eNB's initial boot-up process and a pre-operation phase. In other words, the self-configuration process is a method of self-collecting/analyzing the parameters needed for an eNB's initial operation.
In the self-configuration operation process, after an eNB is powered on and connected to a transport link, the eNB may perform self-detection functions after the basic self-hardware verification. The self-detection functions may include functions of detecting the transport type and the length of an antenna cable, and automatically adjusting the path of a receiver. After performing the self-detection function, the eNB may set up a physical transfer link, and acquire information about its Internet Protocol (IP) address and an IP address to a relevant service or to relevant equipment such as a serving gateway, a Mobility Management Entity (MME), a configuration server, and the like, through a connection to a Dynamic Host Configuration Protocol (DHCP)/Domain Name System (DNS) server. Upon completion of this process, the eNB may create a secure tunnel to be used for S1 and X2 links in preparation for communication with a storage server, from which the eNB can obtain a new parameter set. Neighbor relations may be optionally set through the automated functions.
Automatic Neighbor Relation (ANR) aims to minimize or remove, if possible, the operations on neighbor information when installing a new eNB and optimizing the neighbor information. The ANR function may provide an automated method of acquiring and setting neighbor information to another eNB or a neighbor cell in an eNB or a cell, to which a User Equipment (UE) is currently connected. For the purpose of handover, the ANR function may automatically set an X2 interface that supports an interface between eNBs in Long Term Evolution (LTE).
An Evolved Universal Terrestrial Radio Access (EUTRA) Cell Global ID (ECGI), a Cell Global Identity (CGI), and a Global eNB ID (GEI) needed to set the X2 interface will be described with reference to the following table.
Table 1 illustrates relationships among the ECGI, CGI, and GEI.
TABLE 1EUTRA CELL GLOBAL ID (ECGI)PLMN IDCELL GLOBAL ID (28 bit)MobileMobileeNB ID (20 bit)Cell IDcountry codenetwork code(8 bit)GLOBAL eNB IDPLMN IDMobileMobileeNB IDcountry codenetwork code
The ECGI may include the CGI and the first Public Land Mobile Network ID (PLMN ID) in a Broadcast Public Land Mobile Network ID LIST (BPLMN ID LIST). The BPLMN LIST represents a list of PLMN IDs supported by the cell. Typically, the first PLMN ID may be a PLMN ID of a global eNB ID of an eNB managing the cell and the first PLMN ID may be defined as a Primary PLMN ID. The PLMN ID may include a mobile country code and a mobile network code. The CGI may include an eNB ID and a cell ID, and the cell ID and the eNB ID included in the CGI may be 8 bits and 20 bits in length, respectively. The GEI may include a PLMN ID and an eNB ID of the eNB.
For example, assuming that a first cell operates a first eNB and a second cell operates a second eNB, there is a need for a CGI included in an ECGI of the second cell and a PLMN ID of the second eNB, in order for the first cell to add and manage the second cell as its neighbor cell.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.